MP2607 MPS, MP2607 Datasheet - Page 13

• Manufacturer Part Number: MP2607
• Description: Li + Linear Charger Withsystem Power Path Management
• Manufacturer: MPS

APPLICATION INFORMATION
COMPONENT SELECTION
Battery Charging Current
The
programmable using an external resistor R
at ICHSET pin:
Where 1.260V is an internal reference voltage
for ICHSET programming. Typically R
chosen between 1.51kΩ (1.50A I
(300mA I
However, due to current limit constraint at the
input source, either adapter or USB port input,
the charging current could be less than above
calculated value if system load demand is high.
MP2607 will always ensure the sum of system
load current and charging current complies with
source current limit, with system load has the
priority. Especially for USB mode, when system
load exceeds the source current limit, charging
is actually stopped and battery is pulled in to
supplement the system load.
When using USB port as input source, if the
charging current is set higher than USB port
current limit I
current will not be higher than USB current limit
and could be reduced further if system draws
any load.
End of Charge Threshold Current
The end of charge threshold current is set
internally to be at 10% of I
Where 1.260V is an internal reference voltage
and R
ICHSET pin.
When the charging current falls below I
CV charge mode, MP2607 will terminate
charge, and latch the status pin to indicate the
end of charge.
MP2607 Rev. 1.0
1/5/2011
charging
CHG
CHG
I
).
is the programming resistor at
CHG
I
EOC
USB_MAX
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
=
=
1800
current
180
, then the real charging
×
×
R
1.260V
CHG
R
1.260V
CHG
CHG
:
of
(Ω
(Ω
CHG
)
MP2607 – LI-ION CHARGER WITH POWER PATH MANAGEMENT
)
MP2607
) and 7.5kΩ
© 2011 MPS. All Rights Reserved.
CHG
www.MonolithicPower.com
EOC
CHG
in
is
is
Trickle Charge Current
When the battery voltage is below the minimum
battery voltage V
characteristics table), the charger operates in a
trickle/preconditioning
charging current is typically 7.5% of the
programmed charge current I
Timer for Charge Termination
MP2607 has a built-in timer to terminate the
charge if the timer times out, no matter whether
I
charged full, the timer is reset. This timer is
programmable using an external capacitor C
at TMR pin, to allow user adjust to different
battery capacity. The timer can be calculated
as:
The timer period is strictly inversely proportional
to the real charging current (either in power
path state or CV charge mode). Due to the
power path management function, the real
charging current usually varies during the whole
charging process, thus MP2607 automatically
takes into account this variation and adjust the
timer time out accordingly. Basically the timer
increases the same proportion as the charging
current decreases. If the charging is stopped
due to high system load, the timer is temporarily
suspended. In this way, the actual energy
delivered to the battery, which is charging
current multiplying the charging time, remains
constant.
The time out operation will set the charger into
suspended state and be reported at the status
output pins. To clear the time out status, one
has to recycle the chip enable pin or IN supply.
EOC
is reached or not. And once the battery is
T
TMR
I
TRKL
=
2.3 hours
TH_TRKL
=
150
(defined in the electrical
×
mode,
R
×
1.260V
I
CHG
CHG
1
CHG
(Ω
×
.
C
1 F
)
TMR
µ
where
the
TMR
13